Where do you find the SPOTTER in Arc Raiders?
The SPOTTER spawns on Dam Battlegrounds, The Spaceport, Buried City and The Blue Gate. Spawn points are irregular between raids, so treat the map below as patrol areas rather than fixed positions.

Spotters are flying support drones for the Bombardier. They will point a laser at any Raider in line-of-sight so the Bombardier can accurately target them. If both Spotters are destroyed a new pair will respawn. When the Bombardier is destroyed the Spotters will fly away.
Unarmored thrusters

Landmarks and extractions on Dam Battlegrounds are shown above. Open the full Dam Battlegrounds map for loot containers and quest markers.
The SPOTTER spawns on Dam Battlegrounds, The Spaceport, Buried City and The Blue Gate. Spawn points are irregular between raids, so treat the map below as patrol areas rather than fixed positions.
The SPOTTER is weak to unarmored thrusters. It is rated high threat, so engage it with a plan and an escape route.
The SPOTTER drops ARC Alloy, ARC Powercell, Sensors and Spotter Relay.
Destroying the SPOTTER awards 100 XP, and looting its wreck awards 200 XP.
Killing the SPOTTER is worth 300 XP and drops worth roughly 1,970 in total.
The SPOTTER shares its high threat rating with FIREBALL, HORNET and SENTINEL. Compare their weaknesses and drops before choosing what to engage.